PNL Volume 13 1981
Crowden, R. K. Botany Department, University of Tasmania, Hobart, Australia
The effects of the genes A, Am, Ar, Ce, and Cr on flower color in
Pisum are well-known, at least in qualitative terms (1). During the course
of our studies on anthocyanin biosynthesis, we found it necessary to make
quantitive determinations of pigment production in the different genotypes.
The quantitative data presented in Table I were compiled from a study of
Pisum lines available at the University of Tasmania (collection of Dr. I.
C. Murfet, plus many Weibullsholm lines). All plants used in the study were
grown under glasshouse conditions.
Anthocyanin concentration was determined by reflectance and absorption
spectroscopy of individual flower petals or their extract (in acidified methyl
alcohol), using a Unicam SP8-100 spectrophotometer, with an integrating sphere
diffuse reflectance accessory. The data provided in the table are the mean
values obtained for anthocyanin concentration in each genotype expressed as
a percentage of wild type.
Attention is drawn to the following points in Table I:
1) In am, ar, and ce lines, the pigment content of the standard petals
is consistently about 1/5 - 1/6 the concentration found in the wing petal,
as is the case with wild type flowers; cr lines, however, produce relatively
more pigment in the standard. s/w = 1/3.
2) As well as producing a qualitative effect (cyanidin in place of
delphinidin-type anthocyanin [2]), b causes a marked reduction in the total
amount of anthocyanin produced, particularly in the standard petal. This
quantitive effect is manifest also when other color genes are recessive.
3) Anthocyanin production is negligible in ce cr lines grown under
glasshouse conditions.
1. Blixt, S. 1962. Agri Hort. Genet. 20:95-110.
2. Statham, C. M., R. K. Crowden and J. B. Harborne. 1971. Phytochem.
3. Statham, C. M. 1974. PhD Thesis, University of Tasmania.